Definitions for gas exchange
gas ex·change

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1. Gas exchange

   Gas exchange is the physical process by which gases move passively by diffusion across a surface. For example, this surface might be the air/water interface of a water body, the surface of a gas bubble in a liquid, a gas-permeable membrane, or a biological membrane that forms the boundary between an organism and its extracellular environment. Gases are constantly consumed and produced by cellular and metabolic reactions in most living things, so an efficient system for gas exchange between, ultimately, the interior of the cell(s) and the external environment is required. Small, particularly unicellular organisms, such as bacteria and protozoa, have a high surface-area to volume ratio. In these creatures the gas exchange membrane is typically the cell membrane. Some small multicellular organisms, such as flatworms, are also able to perform sufficient gas exchange across the skin or cuticle that surrounds their bodies. However, in most larger organisms, which have small surface-area to volume ratios, specialised structures with convoluted surfaces such as gills, pulmonary alveoli and spongy mesophylls provide the large area needed for effective gas exchange. These convoluted surfaces may sometimes be internalised into the body of the organism. This is the case with the alveoli, which form the inner surface of the mammalian lung, the spongy mesophyll, which is found inside the leaves of some kinds of plant, or the gills of those molluscs that have them, which are found in the mantle cavity. In aerobic organisms, gas exchange is particularly important for respiration, which involves the uptake of oxygen (O2) and release of carbon dioxide (CO2). Conversely, in oxygenic photosynthetic organisms such as most land plants, uptake of carbon dioxide and release of both oxygen and water vapour are the main gas-exchange processes occurring during the day. Other gas-exchange processes are important in less familiar organisms: e.g. carbon dioxide, methane and hydrogen are exchanged across the cell membrane of methanogenic archaea. In nitrogen fixation by diazotrophic bacteria, and denitrification by heterotrophic bacteria (such as Paracoccus denitrificans and various pseudomonads), nitrogen gas is exchanged with the environment, being taken up by the former and released into it by the latter, while giant tube worms rely on bacteria to oxidize hydrogen sulfide extracted from their deep sea environment, using dissolved oxygen in the water as an electron acceptor. Diffusion only takes place with a concentration gradient. Gases will flow from a high concentration to a low concentration. A high oxygen concentration in the alveoli and low oxygen concentration in the capillaries causes oxygen to move into the capillaries. A high carbon dioxide concentration in the capillaries and low carbon dioxide concentration in the alveoli causes carbon dioxide to move into the alveoli.

WikidataRate this definition:3.0 / 1 vote

1. Gas exchange

   Gas exchange is a biological process through which different gases are transferred in opposite directions across a specialised respiratory surface. Gases are constantly required and produced as a by-product of cellular and metabolic reactions so an efficient system for their exchange is extremely important. It is linked with respiration in animals, and both respiration and photosynthesis in plants. In respiration, oxygen is required to enter cells whilst waste carbon dioxide must be removed – the opposite is true for photosynthesis, where CO2 enters plants and O2 is released. The exchange of gases essentially occurs as a result of diffusion down a concentration gradient – gas molecules moving from an area of high concentration → low concentration.

How to pronounce gas exchange?

1. Alex

   US English

   David

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   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

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   Karen

   Australian

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   Neerja

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   Zira

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   Oliver

   British

   Wendy

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   South African

How to say gas exchange in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of gas exchange in Chaldean Numerology is: 3

2. Pythagorean Numerology

   The numerical value of gas exchange in Pythagorean Numerology is: 4

Examples of gas exchange in a Sentence

1. Varun Puri:

   The lungs in the body are performing a function, they are providing oxygen to the body and they are removing carbon dioxide, they are performing gas exchange, thus there is some degree of stress on the lungs, when they are in the box or on the circuit, there is really no function they are expected to perform.

2. Mark Ostrowski:

   So hospitals, their business is to save lives ; meat and poultry is to produce goods and services ; pipelines are to create gas exchange or oil exchange, those certain industries also may be targeted because maybe they're behind in their [ software ] patching, maybe their cyber program is not quite what it needs to be.

References

1. ^ Wikipedia
   https://en.wikipedia.org/wiki/Gas_Exchange
2. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=gas exchange